Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence
Earthquake locations along the southern Mid-Atlantic Ridge have large uncertainties due to the sparse distribution of permanent seismological stations in and around the South Atlantic Ocean. Most of the earthquakes are associated with plate tectonic processes related to the formation of new oceanic...
Published in: | Journal of Geophysical Research: Solid Earth |
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Online Access: | https://gfzpublic.gfz-potsdam.de/pubman/item/item_5014937 |
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ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_5014937 2023-05-15T18:21:10+02:00 Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence Schlömer, A. Geissler, W. Jokat, W. Jegen, M. 2017 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5014937 unknown info:eu-repo/semantics/altIdentifier/doi/10.1002/2017JB015017 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5014937 Journal of Geophysical Research: Solid Earth info:eu-repo/semantics/article 2017 ftgfzpotsdam https://doi.org/10.1002/2017JB015017 2023-02-06T00:33:48Z Earthquake locations along the southern Mid-Atlantic Ridge have large uncertainties due to the sparse distribution of permanent seismological stations in and around the South Atlantic Ocean. Most of the earthquakes are associated with plate tectonic processes related to the formation of new oceanic lithosphere, as they are located close to the ridge axis or in the immediate vicinity of transform faults. A local seismological network of ocean-bottom seismometers and land stations on and around the archipelago of Tristan da Cunha allowed for the first time a local earthquake survey for 1 year. We relate intraplate seismicity within the African oceanic plate segment north of the island partly to extensional stresses induced by a bordering large transform fault and to the existence of the Tristan mantle plume. The temporal propagation of earthquakes within the segment reflects the prevailing stress field. The strong extensional stresses in addition with the plume weaken the lithosphere and might hint at an incipient ridge jump. An apparently aseismic zone coincides with the proposed location of the Tristan conduit in the upper mantle southwest of the islands. The margins of this zone describe the transition between the ductile and the surrounding brittle regime. Moreover, we observe seismicity close to the islands of Tristan da Cunha and nearby seamounts, which we relate to ongoing tectono-magmatic activity. Article in Journal/Newspaper South Atlantic Ocean GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) Mid-Atlantic Ridge Tristan ENVELOPE(140.900,140.900,-66.735,-66.735) Journal of Geophysical Research: Solid Earth 122 12 10,427 10,439 |
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Open Polar |
collection |
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
op_collection_id |
ftgfzpotsdam |
language |
unknown |
description |
Earthquake locations along the southern Mid-Atlantic Ridge have large uncertainties due to the sparse distribution of permanent seismological stations in and around the South Atlantic Ocean. Most of the earthquakes are associated with plate tectonic processes related to the formation of new oceanic lithosphere, as they are located close to the ridge axis or in the immediate vicinity of transform faults. A local seismological network of ocean-bottom seismometers and land stations on and around the archipelago of Tristan da Cunha allowed for the first time a local earthquake survey for 1 year. We relate intraplate seismicity within the African oceanic plate segment north of the island partly to extensional stresses induced by a bordering large transform fault and to the existence of the Tristan mantle plume. The temporal propagation of earthquakes within the segment reflects the prevailing stress field. The strong extensional stresses in addition with the plume weaken the lithosphere and might hint at an incipient ridge jump. An apparently aseismic zone coincides with the proposed location of the Tristan conduit in the upper mantle southwest of the islands. The margins of this zone describe the transition between the ductile and the surrounding brittle regime. Moreover, we observe seismicity close to the islands of Tristan da Cunha and nearby seamounts, which we relate to ongoing tectono-magmatic activity. |
format |
Article in Journal/Newspaper |
author |
Schlömer, A. Geissler, W. Jokat, W. Jegen, M. |
spellingShingle |
Schlömer, A. Geissler, W. Jokat, W. Jegen, M. Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
author_facet |
Schlömer, A. Geissler, W. Jokat, W. Jegen, M. |
author_sort |
Schlömer, A. |
title |
Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
title_short |
Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
title_full |
Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
title_fullStr |
Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
title_full_unstemmed |
Seismicity in the Vicinity of the Tristan Da Cunha Hot Spot: Particular Plate Tectonics and Mantle Plume Presence |
title_sort |
seismicity in the vicinity of the tristan da cunha hot spot: particular plate tectonics and mantle plume presence |
publishDate |
2017 |
url |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_5014937 |
long_lat |
ENVELOPE(140.900,140.900,-66.735,-66.735) |
geographic |
Mid-Atlantic Ridge Tristan |
geographic_facet |
Mid-Atlantic Ridge Tristan |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
Journal of Geophysical Research: Solid Earth |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1002/2017JB015017 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5014937 |
op_doi |
https://doi.org/10.1002/2017JB015017 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
122 |
container_issue |
12 |
container_start_page |
10,427 |
op_container_end_page |
10,439 |
_version_ |
1766200299351965696 |